Xaccers: I'm assuming the thing nffc suggested is specific to your motherboard [most motherboards usually have a jumper for clearing the CMOS, or in the case of some newer 1s a button on the mobo], but there's something similar you could try. Does your PSU have a power switch on the back? If so, turn it off, then unplug, wait a few secs, plug back in, & turn the switch on again, then try powering up. Don't ask me why, but that's worked on more than 1 machine.
<edit>
Unless you get a second hand or just as-yet-unsold socket 939 board, I doubt you'll find a socket AM2 board that can take PC3200. Having said that, I think there
might be
1, made by Asrock. I know it has the capability to take either a s939 or AM2 CPU [you need to buy a seperate adapter card to use an AM2 with it], &...
<goes & looks>
Ah, yes, I was right about the CPUs, & it
does take DDR1.
That's not a recommendation, BTW - just letting you know there is 1 that will do what you want, no idea what it's like.
</edit>
<edit2>
BTW, it also has both PCI-E & AGP, though you can't use both at the same time.
</edit2>